The present invention relates to a carburetor for an internal combustion engine and, more particularly, to a float chamber means for the carburetor.
A carburetor incorporated in the internal combustion engine of an automobile is cooled during operation of the engine by the draught generated by the radiator cooling fan and also by the flow of intake air, and heat absorbing vaporization of liquid fuel. Furthermore, when the automobile is running, the cooling effect applied to the carburetor is increased by the draught caused by the running of the automobile. Due to these cooling functions the carburetor is generally maintained at a moderate temperature which does not cause abnormal vaporization of fuel flowing through the passages formed therein. However, when the engine has been abruptly put into idling operation or stopped after high speed, high load operation, the temperature of the engine and of the air existing in the engine compartment temporarily rises so high that it often causes percolation due to abnormal vaporization of liquid fuel in the passages provided in the carburetor. Such a percolation is principally caused by highly volatile components included in liquid fuel such as gasoline. The conventional method for avoiding percolation is generally to improve the cooling effect applied to the carburetor by employing various cooling means. However, the conventional cooling method is still not sufficient to suppress completely the occurrence of percolation in carburetors.